Are there draw conditions in the game? Or more exactly, if no faction can achieve any of their victory conditions (and in later scenarios and SAGS, have equal MP), what happens?

The originating situation in Tutorial Scenario #2:

Salemite forces have completely blocked entry to the small door into the chapel. All Salemite forces are Healthy, and have few, if any wound counters. A Wounded Nick Bolter is surrounded by Hollister, Jack Saw and a Zombie in the intersection between the stairwell and the Chapel. James Woo is being pursued by the other Zombie, but could get to either the main doors into the Chapel, or escape the board. Vasquez might be able to enter the Chaplain's Bedroom (the bedroom attached to the Chapel), but Jack Saw can reach it before she can, she can also escape.

Bolter and Woo together manage to free Bolter by destroying the one Zombie. At this point, the NORAD player realizes that Bolter is too close to dying (and granting the Salemites victory), so he flees. Neither Woo or Vasquez are capable to fighting Jack Saw or Hollister, or breaking down any of the doors. So they flee as well.

The result: All NORAD characters are alive, and cannot be killed by the Salemites, so no Salemite victory is possible. On the other hand, the NORAD characters cannot reenter the board, so none of them can enter the Chapel (much less the two required), so no NORAD victory is possible.

Is this a Draw? A simultaneous Loss for both factions? A Loss for NORAD? A Loss for the Salemites?